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<body><h1><a href="http://ejohn.org/blog/processingjs/">Processing.js</a></h1>
<h2>Conway</h2>

<p>by Mike Davis. 

This program is a simple version of Conway's 
game of Life.  A lit point turns off if there 
are fewer than two or more than three surrounding 
lit points.  An unlit point turns on if there 
are exactly three lit neighbors.  The 'density' 
parameter determines how much of the board will 
start out lit.</p>

<p><a href="http://processing.org/learning/topics/conway.html"><b>Original Processing.org Example:</b> Conway</a><br>
<script type="application/processing">
int sx, sy; 
float density = 0.5; 
int[][][] world;
 
void setup() 
{ 
  size(100, 100);
  frameRate(12);
  sx = width;
  sy = height;
  world = new int[sx][sy][2]; 
  stroke(255); 
   
  // Set random cells to 'on' 
  for (int i = 0; i < sx * sy * density; i++) { 
    world[(int)random(sx)][(int)random(sy)][1] = 1; 
  } 
} 
 
void draw() 
{ 
  background(0); 
  
  // Drawing and update cycle 
  for (int x = 0; x < sx; x=x+1) { 
    for (int y = 0; y < sy; y=y+1) { 
      //if (world[x][y][1] == 1) 
      // Change recommended by The.Lucky.Mutt
      if ((world[x][y][1] == 1) || (world[x][y][1] == 0 && world[x][y][0] == 1)) 
      { 
        world[x][y][0] = 1; 
        point(x, y); 
      } 
      if (world[x][y][1] == -1) 
      { 
        world[x][y][0] = 0; 
      } 
      world[x][y][1] = 0; 
    } 
  } 
  // Birth and death cycle 
  for (int x = 0; x < sx; x=x+1) { 
    for (int y = 0; y < sy; y=y+1) { 
      int count = neighbors(x, y); 
      if (count == 3 && world[x][y][0] == 0) 
      { 
        world[x][y][1] = 1; 
      } 
      if ((count < 2 || count > 3) && world[x][y][0] == 1) 
     { 
        world[x][y][1] = -1; 
      } 
    } 
  } 
} 
 
// Count the number of adjacent cells 'on' 
int neighbors(int x, int y) 
{ 
  return world[(x + 1) % sx][y][0] + 
         world[x][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][y][0] + 
         world[x][(y + sy - 1) % sy][0] + 
         world[(x + 1) % sx][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][(y + sy - 1) % sy][0] + 
         world[(x + 1) % sx][(y + sy - 1) % sy][0]; 
}
</script><canvas width="200" height="200"></canvas></p>
<div style="height:0px;width:0px;overflow:hidden;"></div>

<pre><b>// All Examples Written by <a href="http://reas.com/">Casey Reas</a> and <a href="http://benfry.com/">Ben Fry</a>
// unless otherwise stated.</b>
int sx, sy; 
float density = 0.5; 
int[][][] world;
 
void setup() 
{ 
  size(100, 100);
  frameRate(12);
  sx = width;
  sy = height;
  world = new int[sx][sy][2]; 
  stroke(255); 
   
  // Set random cells to 'on' 
  for (int i = 0; i &lt; sx * sy * density; i++) { 
    world[(int)random(sx)][(int)random(sy)][1] = 1; 
  } 
} 
 
void draw() 
{ 
  background(0); 
  
  // Drawing and update cycle 
  for (int x = 0; x &lt; sx; x=x+1) { 
    for (int y = 0; y &lt; sy; y=y+1) { 
      //if (world[x][y][1] == 1) 
      // Change recommended by The.Lucky.Mutt
      if ((world[x][y][1] == 1) || (world[x][y][1] == 0 && world[x][y][0] == 1)) 
      { 
        world[x][y][0] = 1; 
        point(x, y); 
      } 
      if (world[x][y][1] == -1) 
      { 
        world[x][y][0] = 0; 
      } 
      world[x][y][1] = 0; 
    } 
  } 
  // Birth and death cycle 
  for (int x = 0; x &lt; sx; x=x+1) { 
    for (int y = 0; y &lt; sy; y=y+1) { 
      int count = neighbors(x, y); 
      if (count == 3 && world[x][y][0] == 0) 
      { 
        world[x][y][1] = 1; 
      } 
      if ((count &lt; 2 || count &gt; 3) && world[x][y][0] == 1) 
     { 
        world[x][y][1] = -1; 
      } 
    } 
  } 
} 
 
// Count the number of adjacent cells 'on' 
int neighbors(int x, int y) 
{ 
  return world[(x + 1) % sx][y][0] + 
         world[x][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][y][0] + 
         world[x][(y + sy - 1) % sy][0] + 
         world[(x + 1) % sx][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][(y + 1) % sy][0] + 
         world[(x + sx - 1) % sx][(y + sy - 1) % sy][0] + 
         world[(x + 1) % sx][(y + sy - 1) % sy][0]; 
}</pre>
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